RETRACTED: Modified Closing-Opening Wedge Osteotomy to Correct Kyphosis in Ankylosing Spondylitis (Retracted Article)

Background: The aim of this study was to analyze the clinical and radiological outcomes of modified closing-opening wedge osteotomy (mCOWO) for correcting kyphosis in ankylosing spondylitis (AS) patients. Material/Methods: From April 2012 to April 2017, records of consecutive patients who underwent mCOWO were reviewed. The clinical and radiological outcomes were analyzed preoperatively, postoperatively, and at the most recent follow-up. Results: Eleven AS patients underwent mCOWO, with a mean follow-up of 19.4 months (range, 12-45 months). The average sagittal vertical axis (SVA) was corrected from 191.9 mm preoperatively to 75.9 mm postoperatively (P<0.05) and 78.9 mm at the most recent follow-up (P<0.05). The average correction angles at the osteotomy site were 44.5 degrees postoperatively and 45.0 degrees at the most recent follow-up (P>0.05). Sagittal translation (ST) occurred in 2 patients, and 5 mm was the maximum. There was no neurologic damage. Solid fusion was observed at the most recent follow-up in all patients. Conclusions: Modified closing-opening wedge osteotomy (mCOWO) is an effective technique for correcting kyphosis in patients with AS.